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    <title>Document</title>
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    <script>
        /* 
        1.遍历数组， 直接遍历
        2.for 循环， 遍历索引号
        3.数组的长度作为索引号
        */
        //1. 直接遍历
        let arr = ['早上好', '中午好', 11, 12, true];
        console.log(arr[0]);
        console.log(arr[1]);
        console.log(arr[2]);
        console.log(arr[3]);
        console.log(arr[4]); 
        //2. for循环，遍历索引号
        for (let i = 0; i <= 4; i++) {
            //console.log(i);只有序号运行
            console.log(arr[i]);//遍历所有元素
        }
        //3.数组的长度作为计数器
        for (let i = 0; i < arr.length; i++) { //小于数组长度
            console.log(arr[i]);
        }
    </script>
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